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S Paine

Publications and source records attributed to S Paine.

12 recordsLinked to original sources

Interpretation variability of 18FDG-positron emission tomography studies in dementia.

RATIONALE AND OBJECTIVES: Functional imaging studies such as 18F-fluoro-18-labeled-deoxyglucose-positron emission tomography (18FDG-PET) are being used increasingly in the evaluation of patients with dementia. The authors evaluate inter- and intraobserver interpretation agreement in a diverse group of patients with clinically diagnosed dementia and subjective memory complaints, as well as two healthy control subjects. METHODS: Ninety-six patients with clinical diagnoses of probable Alzheimer's disease (n = 18), possible Alzheimer's disease (n = 33), dementia (n = 26), and mild memory impairment (n = 17), as well as two healthy control subjects were studied using 18FDG-PET. Three observers graded all studies for regional 18FDG uptake in the temporal, parietal, and frontal regions bilaterally. The studies also were interpreted for the presence of bilateral temporoparietal hypometabolism, which typically is present in Alzheimer's disease. The kappa statistic was used to determine intra- and interobserver agreement for regional 18FDG uptake and bilateral temporoparietal hypometabolism. RESULTS: There was excellent intraobserver (kappa = .56, P < 0.0005) and interobserver (kappa = .51, P < 0.0005) interpretation agreement for bilateral temporoparietal hypometabolism. There also was excellent intraobserver (kappa = .61, P < 0.000) and interobserver (kappa = .55, P < 0.000) interpretation agreement of regional 18FDG uptake. Interobserver agreement was extremely high in those patients who were considered clinically to have possible (kappa = .42, P < 0.001) or probable (kappa = .42, P < 0.01) Alzheimer's disease. CONCLUSIONS: Results confirm that bilateral temporoparietal hypometabolism is the metabolic abnormality associated with the diagnosis of probable Alzheimer's disease. Furthermore, intra- and interobserver agreement of visual interpretation of 18FDG-PET images indicates that 18FDG-PET is acceptable as an imaging technique in the clinical evaluation of the dementia patient.

Adult

Significance of percutaneous needle biopsy in patients with multiple pulmonary nodules and a single known primary malignancy.

OBJECTIVE: To determine the necessity of percutaneous lung biopsy in patients with a single known primary malignancy and multiple pulmonary nodules. DESIGN: Retrospective study. SETTING: Tertiary care university hospital. RESULTS: We reviewed all percutaneous lung biopsy specimens over a 6-year period. One hundred forty-six patients with a single known primary malignancy and multiple pulmonary nodules had biopsies performed up to 19 years following diagnosis of the primary neoplasm. One hundred thirty-seven biopsy specimens (93.8%) were positive for metastases. Eight patients (5.5%) had a nondiagnostic biopsy specimen; however, subsequent imaging studies and the clinical course strongly suggested diffuse metastatic disease. One patient (< 1%) with breast carcinoma developed nodules 3 years after initial diagnosis and had resolution without a definitive diagnosis or therapy. CONCLUSION: Patients with a single known primary malignancy and multiple pulmonary nodules who present for percutaneous needle biopsy will have pulmonary metastases in the vast majority of cases. Biopsy in these patients rarely changes the clinical course as other diagnoses are rarely established.

Adolescent

A report of the findings of a 1-year study of the waiting times among patients attending an accident and emergency department.

The aim of this study was to enable a research-based standard to be set in relation to waiting times. This would be in accordance with the recommendations of the Patient's Charter (Department of Health 1992). The study was undertaken with the cooperation of the staff of the Accident and Emergency (A & E) department, within an acute unit in the Oxford region. Between 1 January and 31 December 1992 a random sample of 230 casualty cards were drawn and analyzed. Analysis showed that 90.5% of patients in the sample were assessed by a nurse at or within 10 minutes of arrival, and 83.25% of patients in the sample were seen by the doctor at or within 60 minutes of arrival.

Adolescent

Evaluation of revised criteria for ventilation-perfusion scintigraphy in patients with suspected pulmonary embolism.

PURPOSE: To evaluate the accuracy of the revised PIOPED (Prospective Investigation of Pulmonary Embolism Diagnosis) criteria for categorization of ventilation-perfusion lung scans and to compare the diagnostic accuracy of the revised criteria with that of the original PIOPED criteria and subjective probability estimates. MATERIALS AND METHODS: The ventilation-perfusion scans of 104 consecutive patients with suspected pulmonary embolism were reviewed. All patients had also undergone pulmonary angiography. The scans were categorized according to the original and revised PIOPED criteria, and a "gestalt" percent probability estimate was made. In addition, the official clinical interpretation (made with the original PIOPED criteria) was recorded. RESULTS: The gestalt percent probability estimate was the most accurate for assessing the likelihood of pulmonary embolism (area under the receiver operating characteristic [ROC] curve = 0.836). The revised PIOPED criteria (area under the ROC curve = 0.753) were more accurate than the original PIOPED criteria. CONCLUSION: The revised PIOPED criteria are more accurate than the original PIOPED criteria. Experienced readers of lung scans can achieve higher accuracy after applying formal criteria by using their experience and subjective judgment.

Evaluation Studies as Topic

MR and positron emission tomography in the diagnosis of surgically correctable temporal lobe epilepsy.

PURPOSE: To determine the association of an MR abnormality and a positron emission tomography (PET) abnormality with a good outcome in patients with temporal lobe epilepsy after lobectomy, the association of combined PET and MR findings with good outcomes after lobectomy, and MR and PET pathologic correlation. METHODS: MR and PET were performed on 27 patients in a blinded study. Histologic studies were correlated with foci of increased T2 signal. RESULTS: Increased signal or decreased volume of the hippocampus was noted in 13 of 15 patients with mesial temporal sclerosis. Twelve of 15 had positive PET findings. MR identified 20 (83%) of the 24 patients with good outcomes. PET identified 71%. When MR and PET were combined, they detected 95% of the patients with good outcome. Region of interest measurements of the hippocampus in 11 study patients and 7 control subjects documented a significant increase in signal in the patients with seizures. Histologic correlative studies demonstrated that increased T2 signals related to astrocytosis in the hippocampus and adjacent white matter. CONCLUSIONS: MR (increased signal and decreased volume of the hippocampus) significantly improved the capability to identify those persons who would be helped by lobectomy. MR sensitivity exceeded that of PET.

Adolescent

Cerebral imaging of decompression injury patients with 18-F-2-fluoro-2-deoxyglucose positron emission tomography.

The objective assessment of the extent of cerebral insult and the effects of therapy in decompression injury patients has proven to be difficult by most imaging modalities. In this pilot study we evaluated the ability of 18-F-2-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) to identify metabolic brain abnormalities in decompression injury patients. Twenty-two patients who were evaluated at our institution for decompression accidents were evaluated with FDG-PET. Four of the 22 patients had no neurologic symptoms and no neurologic findings on clinical exam at the time of the FDG-PET study. No statistically significant correlations were found between the presence of symptoms and the demonstration of abnormalities on the PET study and no statistically significant correlation was found between the location of the decompression injury and the demonstration of abnormalities on the PET study. We conclude that FDG-PET imaging of the brain cannot reliably identify cerebral abnormalities in patients with decompression injuries and would be of limited benefit for monitoring therapy in patients with decompression illness.

Adult

Stent placement for benign pancreatic diseases: correlation between ERCP findings and clinical response.

OBJECTIVE: We performed a study to determine if the appearance of the pancreatic duct on ERCP before and after placement of pancreatic duct stents correlates with the therapeutic response in patients treated for impaired pancreatic drainage. MATERIALS AND METHODS: Findings in 29 consecutive patients with a variety of benign pancreatic diseases in whom pancreatic stents were placed and subsequently removed within a 3-year period were reviewed retrospectively. Early (1-5 days) and late (1-3 months) clinical outcomes after stent placement were assessed. These findings were correlated with a blinded interpretation of ERCP findings (Cambridge criteria were used) before and after stent placement. RESULTS: ERCP findings before stent placement were normal in 10 patients. At the end of stent therapy, ERCP showed changes associated with chronic pancreatitis in all 10; five had focal narrowing at the tip of the stent. Subsequent ERCP studies in five of these 10 patients showed that ductal changes induced by stents diminished after stent removal. Of the 19 patients with abnormal findings on ERCP at the time of stent placement, ERCP at the end of stent therapy showed some improvement in seven patients, no change in eight, and deterioration in four. Changes seen on ERCP had no statistically significant correlation with clinical outcome (p = .36). CONCLUSION: Our findings show that pancreatic duct stents can induce abnormalities on ERCP indicative of chronic pancreatitis. However, diminution of these abnormalities after stent removal in some patients suggests that these changes may be due to edema rather than to fibrosis. Ductal changes seen on ERCP are not a useful guide for determining the degree of response to pancreatic stents.

Cholangiopancreatography, Endoscopic Retrograde

Serial FDG-PET studies in the prediction of survival in patients with primary brain tumors.

OBJECTIVE: This study examines the changes in tumor [18F]fluoro-2-deoxyglucose (FDG) uptake on serial FDG-PET studies and the ability of serial FDG-PET studies to predict survival in patients with treated and untreated primary brain tumors. MATERIALS AND METHODS: The study population included 20 patients with primary brain tumors. Changes in FDG uptake over time were visually assessed and correlated with clinical course and survival. RESULTS: Although little change in FDG uptake was noted for individual patients, high average FDG uptake (greater than or equal to gray matter) on serial studies was associated with shorter survival. Patients with persistently low FDG uptake (less than gray matter) survived significantly longer than patients with persistently high FDG uptake (p = 0.007). CONCLUSION: Serial evaluation of metabolic activity with PET may provide more accurate prognostic information than a single FDG uptake determination in patients with primary brain tumors.

Adult

The diagnostic accuracy/efficacy of MRI in differentiating hepatic hemangiomas from metastatic colorectal/breast carcinoma: a multiple reader ROC analysis using a jackknife technique.

PURPOSE: Our purpose was to determine the diagnostic accuracy efficacy of a simple MR technique in differentiating hepatic hemangiomas from colorectal or breast metastases using a multiple reader method. METHOD: Thirty-seven cases with confirmed hepatic hemangiomas and 115 with confirmed hepatic metastases (colon primary, n = 86; breast primary, n = 29) evaluated with MRI at 1.5 T were retrospectively collected. A single lesion in a single slice from each patient was randomly selected; the images were masked and then were interpreted in random order by five separate readers blinded to the diagnosis using a five point diagnostic scale (from definite hemangioma to definite metastasis). Morphologic characteristics of lesion margin, signal intensity relative to other structures, and internal architecture (homogeneous versus heterogeneous) were also assessed independently of the five point diagnostic scale. Three of the readers had > 8 years of experience, while the other two had 1 and 3 years. The diagnostic scale results were subjected to receiver operating characteristic (ROC) analysis using a jackknife method. kappa-Statistics were applied to assess interreader agreement in the morphologic characteristics. A logistic regression model was used to determine which characteristics predicted pathology and reader diagnosis. RESULTS: ROC analysis showed the average area under the curve over all readers was (0.91 (0.89-0.93 95% confidence interval) (p < 0.0001). An analysis of variance showed no significant difference between the areas under the curves of each reader (p = 0.6433). When the definite and probable categories for hemangioma and metastasis were combined, the sensitivity/specificity for the diagnosis of hemangioma ranged from 57 to 73%/91 to 97%. The positive/negative predictive value ranged from 72 to 84%/87 to 91%. For the morphologic assessment, there was significant agreement between the readers (p < 0.0001-0.0037). A sharp margin and lesion signal equal to or greater than CSF predicted the presence of a hemangioma (p = 0.0148 and p < 0.0001, respectively). A sharp margin, lesion signal equal to or greater than CSF, and a homogeneous internal architecture all predicted the reader diagnosis of definitely or probably hemangioma. CONCLUSION: For multiple readers, T2-weighted SE MRI alone is a very specific method for distinguishing hemangiomas from metastatic colon or breast carcinoma. Morphologic characteristics of a sharp margin and a high signal predict the presence of a hemangioma. Last, reader experience does not appear to have a significant effect on the specificity.

Adult

AIDS in drug abusers.

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Acquired Immunodeficiency Syndrome